A high-frequency output apparatus 12 and an ultrasound output apparatus 15, which are medical apparatuses, each has a CPU 28, 42, a communication circuit 31, 49 and a speaker 18, 19. Each CPU transmits, when an output volume level of a sound outputted from its own speaker is changed, information about the changed output volume level to the other medical apparatus from the communication circuit, and controls output volume of the sound outputted from its own speaker on the basis of output volume information about a sound outputted of the speaker of the other apparatus, which has been received in the communication circuit.
